As the division is performed, find the first time that the carry repeats itself.

7 into 2...doesn't divide
7 into 20 is 2 rem 6.

First carry is 6, so the next division is 7 into 60

7 into 60 is 8 rem 4
7 into 40 is 5 rem 5
7 into 50 is 7 rem 1
7 into 10 is 1 rem 3
7 into 30 is 4 rem 2
7 into 20.... there is where the pattern repeats since we always have a zero after the remainder
for the next division,